1. Field of the Invention
The present invention relates generally to wrenches and more particularly to a ratcheting type pipe wrench having cooperating, relatively moveable pipe gripping jaws one of which is rotatable and the other of which is nonrotatable.
2. Discussion of the Prior Art
Pipe wrenches of various design have been suggested in the past including pipe wrenches having one fixed and one rotating type jaw. Wrenches of this type are disclosed in U.S. Pat. Nos. 1,195,558; 1,593,588; and 2,446,212.
Common to the prior art wrenches disclosed in the aforementioned patents and common to all wrenches of this general type of which the inventor is aware, is the provision of an elongated handle having a fixed jaw at its forward end and a reciprocating jaw adapted to move longitudinally of the handle. Frequently the handle is provided with a gear rack along which the reciprocating jaw rolls. The advantage of wrenches of this character over the traditional Stillson wrench is the ease of rapid adjustment of the jaws for initial engagement with different sizes of pipe. The drawback of such wrenches, however, resides in the fact that, while the rotating jaw is readily movable in a longitudinal direction relative to the fixed jaw, it is incapable of a pivotal or rocking type movement relative to the fixed jaw. This somewhat reduces the gripping effectiveness of the wrench since pressure on the handle will not tend to tighten the jaws about the work piece and, in fact, could cause loosening of the jaws. Additionally, since the movable jaw is typically biased toward the fixed jaw any ratcheting type action of the wrench is severely inhibited because a release of pressure on the handle will not automatically cause the jaws to loosen their grip upon the work piece. Further, the wrench must be manually adjusted to different sizes and will not ratchet on any shape other than a round pipe shape.
The wrench of the present invention effectively overcomes the drawbacks of the prior art designs by providing a wrench which, due to its unique configuration, accomodates longitudinal as well as rotational or pivotal degrees of movement of the gripping jaws relative to the work piece. the ability of the jaws to be readily separated longitudinally enables rapid and easy adjustment of the jaws for initial gripping of workpiece of widely differing diameters. The fact that the fixed jaw is formed on a part which is independently movable relative to the handle portion, however, permits relative pivotal or rocking movement of the jaws so that pressure exerted on the handle will tend to increasingly tighten the jaws about the work piece. Conversely, release of pressure on the handle will cause the jaws to automatically loosen their grip on the pipe so that the wrench can readily be ratcheted to a new gripping position.
In addition to the aforementioned patents, the following United States patents, believed pertinent to the invention clearly demonstrate the novelty of the wrench of the present invention: Nos. 710,179; 594,775; and 1,027,161.